Difference between Hardwired and Micro programmed control unit

Last Updated on 6 years ago by Sumi

Hardwired control unit:

• It is a unit that uses combinational logic units featuring a finite number of gates that can generate specific results, based on instructions that were used to invoke those responses.
• The speed of the operation is fast.
• Here, for the modification, the entire unit should be redesigned.
• They are more costly to implement.
• It is difficult to handle complex instructions.
• It is difficult to perform information Decoding.
• They use a small instruction set.
• There is no control memory usage.
• They are used in processors that use a simple instruction set known as the reduced instruction set computers(RISC).
• They are not flexible.
• Here, the sequential circuit is used.
• Here, The designing process is complicated.

Micro programmed control unit:

• It is a unit that contains microinstructions in the control memory to produce control signals.
• The speed of operation is slow because it requires frequent memory access.
• Here, modifications can be implemented by changing the microinstructions in the control memory.
• They are less costly to implement.
• It is easier to handle complex instructions.
• It is less difficult to perform information Decoding.
• They use a large instruction set.
• They use control memory.
• They are used in processors based on complex instructions set known as complex instruction set computers(CISC).
• They are flexible.
• Here, a programming circuit is used.
• Here, The designing process is systematic.